+
−/*
+
−* OpenAL Bridge - a simple portable library for OpenAL interface
+
−* Copyright (c) 2009 Vittorio Giovara <vittorio.giovara@gmail.com>
+
−*
+
−* This program is free software; you can redistribute it and/or modify
+
−* it under the terms of the GNU Lesser General Public License as published by
+
−* the Free Software Foundation; version 2 of the License
+
−*
+
−* This program is distributed in the hope that it will be useful,
+
−* but WITHOUT ANY WARRANTY; without even the implied warranty of
+
−* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+
−* GNU Lesser General Public License for more details.
+
−*
+
−* You should have received a copy of the GNU Lesser General Public License
+
−* along with this program; if not, write to the Free Software
+
−* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
+
−*/
+
−
+
−#include "openalbridge.h"
+
−#include "globals.h"
+
−#include "al.h"
+
−#include "alc.h"
+
−#include "wrappers.h"
+
−#include "loaders.h"
+
−#include "string.h"
+
−
+
−// Sources are points emitting sound, their number is limited, but a single source can play many buffers
+
−// Buffers hold sound data and are unlimited
+
−ALuint *Sources;
+
−ALuint cache_size, cache_index, sources_number;
+
−ALboolean instances_number;
+
−al_sound_t *the_sounds;
+
−ALint cache_pointer;
+
−
+
−// Initialize an OpenAL contex and allocate memory space for data and buffers
+
−// It can be called twice to increase the cache size
+
−int openal_init (void) {
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−    ALCcontext *context;
+
−    ALCdevice *device;
+
−    int i;
+
−
+
−    // reuse old context and resize the existing
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−    if (openal_ready() == AL_TRUE) {
+
−        fprintf(stderr,"(Bridge Info) - already initialized\n");
+
−        instances_number++;
+
−        return AL_TRUE;
+
−    }
+
−
+
−    cache_pointer = 0;
+
−    instances_number++;
+
−
+
−    // initial memory size
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−    cache_size = 50;
+
−
+
−    // open hardware device if present
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−    device = alcOpenDevice(NULL);
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−    sources_number = 16;
+
−    if (device == NULL) {
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−        fprintf(stderr,"(Bridge Warning) - failed to open sound device, using software renderer\n");
+
−        device = alcOpenDevice("Generic Software");
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−        sources_number = 32;
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−        if (device == NULL) {
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−            fprintf(stderr,"(Bridge ERROR) - failed to start software renderer, sound will be disabled\n");
+
−            return -1;
+
−        }
+
−    }
+
−
+
−    fprintf(stderr,"(Bridge Info) - output device: %s\n", alcGetString(device, ALC_DEVICE_SPECIFIER));
+
−
+
−    context = alcCreateContext(device, NULL);
+
−    alcMakeContextCurrent(context);
+
−    alcProcessContext(context);
+
−
+
−    if (AL_NO_ERROR != alGetError()) {
+
−        fprintf(stderr,"(Bridge ERROR) - Failed to create a new contex\n");
+
−        alcMakeContextCurrent(NULL);
+
−        alcDestroyContext(context);
+
−        alcCloseDevice(device);
+
−        return -2;
+
−    }
+
−
+
−    Sources = (ALuint *)Malloc (sizeof(ALuint) * sources_number);
+
−    alGenSources(sources_number, Sources);
+
−
+
−    // set the listener gain, position (on xyz axes), velocity (one value for each axe) and orientation
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−    // Position, Velocity and Orientation of the listener
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−    ALfloat ListenerPos[] = {0.0, 0.0, 0.0};
+
−    ALfloat ListenerVel[] = {0.0, 0.0, 0.0};
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−    ALfloat ListenerOri[] = {0.0, 0.0, -1.0, 0.0, 1.0, 0.0};
+
−
+
−    alListenerf (AL_GAIN,        1.0f       );
+
−    alListenerfv(AL_POSITION,    ListenerPos);
+
−    alListenerfv(AL_VELOCITY,    ListenerVel);
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−    alListenerfv(AL_ORIENTATION, ListenerOri);
+
−
+
−    if (AL_NO_ERROR != alGetError()) {
+
−        fprintf(stderr,"(Bridge ERROR) - Failed to set Listener properties\n");
+
−        return -3;
+
−    }
+
−
+
−    the_sounds = (al_sound_t *)Malloc (sizeof(al_sound_t) * cache_size);
+
−    for (i = 0; i < cache_size; i++)
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−        the_sounds[i] = new_sound_el();
+
−
+
−    alGetError();
+
−    return AL_TRUE;
+
−}
+
−
+
−
+
−// Stop all sounds, deallocate all memory and close OpenAL context
+
−void openal_close (void) {
+
−    ALCcontext *context;
+
−    ALCdevice  *device;
+
−    int i;
+
−
+
−    if (instances_number == 0) {
+
−        fprintf(stderr,"(Bridge Warning) - OpenAL not initialized\n");
+
−        return;
+
−    }
+
−
+
−    instances_number--;
+
−    if (instances_number > 0) {
+
−        // release memory only when last session ends
+
−        return;
+
−    }
+
−
+
−    for (i = 0; i < cache_size; i++) {
+
−        openal_unloadfile(i);
+
−    }
+
−    free(the_sounds);
+
−
+
−    alSourceStopv (sources_number, Sources);
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−    alDeleteSources (sources_number, Sources);
+
−
+
−    free(Sources);
+
−
+
−    context = alcGetCurrentContext();
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−    device  = alcGetContextsDevice(context);
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−
+
−    alcMakeContextCurrent(NULL);
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−    alcDestroyContext(context);
+
−    alcCloseDevice(device);
+
−
+
−    fprintf(stderr,"(Bridge Info) - closed\n");
+
−
+
−    return;
+
−}
+
−
+
−
+
−ALboolean openal_ready (void) {
+
−    if (instances_number >= 1)
+
−        return AL_TRUE;
+
−    else
+
−        return AL_FALSE;
+
−}
+
−
+
−
+
−// Open a file, load into memory and allocate the Source buffer for playing
+
−int openal_loadfile (const char *filename){
+
−    ALenum format, error;
+
−    ALsizei bitsize, freq;
+
−    uint32_t fileformat;
+
−    al_sound_t sound_data;
+
−    int len, i, index = -1;
+
−    char *data;
+
−    FILE *fp;
+
−
+
−    if (openal_ready() == AL_FALSE) {
+
−        fprintf(stderr,"(Bridge Warning) - not initialized\n");
+
−        return -1;
+
−    }
+
−
+
−    // if this sound is already loaded return the index from the_sounds
+
−    len = strlen(filename);
+
−    for (i = 0; i < cache_size; i++) {
+
−        if (the_sounds[i].filename != NULL && strncmp(the_sounds[i].filename, filename, len) == 0) {
+
−#ifdef DEBUG
+
−            fprintf(stderr,"(Bridge Debug) - sound %d is already loaded\n", i);
+
−#endif
+
−            return i;
+
−        }
+
−        // if we don't have memory available search for a free element
+
−        if (cache_pointer >= cache_size)
+
−            if (the_sounds[i].is_used == AL_FALSE)
+
−                index = i;
+
−    }
+
−
+
−    if (index == -1 && cache_pointer >= cache_size) {
+
−        fprintf(stderr,"(Bridge Info) - No free spots found; doubling cache size\n", filename);
+
−        cache_size *= 2;
+
−        the_sounds = (al_sound_t *)Realloc (the_sounds, sizeof(al_sound_t) * cache_size);
+
−        for (i = cache_size - 50; i < cache_size; i++)
+
−            the_sounds[i] = new_sound_el();
+
−    } else
+
−        index = ++cache_pointer;
+
−
+
−
+
−    // detect the file format, as written in the first 4 bytes of the header
+
−    fp = Fopen (filename, "rb");
+
−    if (fp == NULL) {
+
−        fprintf(stderr,"(Bridge ERROR) - File %s not loaded\n", filename);
+
−        return -3;
+
−    }
+
−
+
−    error = fread (&fileformat, sizeof(uint32_t), 1, fp);
+
−    fclose (fp);
+
−    if (error < 0) {
+
−        fprintf(stderr,"(Bridge ERROR) - File %s is too short\n", filename);
+
−        return -4;
+
−    }
+
−
+
−    switch (ENDIAN_BIG_32(fileformat)) {
+
−        case OGG_FILE_FORMAT:
+
−            error = load_oggvorbis (filename, &format, &data, &bitsize, &freq);
+
−            break;
+
−        case WAV_FILE_FORMAT:
+
−            error = load_wavpcm (filename, &format, &data, &bitsize, &freq);
+
−            break;
+
−        default:
+
−            fprintf(stderr,"(Bridge ERROR) - File format (%08X) not supported\n", ENDIAN_BIG_32(fileformat));
+
−            return -5;
+
−            break;
+
−    }
+
−
+
−    if (error != 0) {
+
−        fprintf(stderr,"(Bridge ERROR) - error loading file %s\n", filename);
+
−        if(data)
+
−            free(data);
+
−        return -6;
+
−    }
+
−
+
−    // alGenBuffers happens here
+
−    sound_data = init_sound_el(filename);
+
−
+
−    if (AL_NO_ERROR != alGetError()) {
+
−        fprintf(stderr,"(Bridge ERROR) - Failed to allocate memory for buffer %d\n", index);
+
−        free(data);
+
−        return -5;
+
−    }
+
−
+
−    // copy pcm data in one buffer and free it
+
−    alBufferData(sound_data.buffer, format, data, bitsize, freq);
+
−    free(data);
+
−
+
−    if (AL_NO_ERROR != alGetError()) {
+
−        fprintf(stderr,"(Bridge ERROR) - Failed to write data to buffer %d\n", index);
+
−        return -8;
+
−    }
+
−
+
−    // clear any AL errors beforehand
+
−    alGetError();
+
−
+
−    fprintf(stderr,"(Bridge Info) - successfully loaded %s\n", filename);
+
−
+
−    // returns the index of the source you just loaded, increments it and exits
+
−    the_sounds[index] = sound_data;
+
−    return index;
+
−}
+
−
+
−
+
−void openal_unloadfile (uint32_t index) {
+
−    ALint state;
+
−
+
−    if (openal_ready() == AL_TRUE && index < cache_size && the_sounds[index].is_used == AL_TRUE) {
+
−        alGetSourcei (Sources[the_sounds[index].source_index], AL_SOURCE_STATE, &state);
+
−        if (state == AL_PLAYING || state == AL_PAUSED)
+
−            openal_stopsound(index);
+
−
+
−        // free memory and
+
−        alDeleteBuffers (1, &the_sounds[index].buffer);
+
−        the_sounds[index] = new_sound_el();
+
−    }
+
−}